Question: Why must God’s truth be revealed via one individual (who then becomes the authority figure) every few thousand years? In other words, why does God not reveal truth to every individual to the extent that that individual can understand it? –Sidfaiwu
Answer: Baha’u'llah teaches that God is an unknowable essence. Being outside "that which is", and having created such, God is indescribable by "that which is" except by analogy. Think of a physicist trying to describe the universe before the Big Bang. Because every quantum of energy/mass passed through a single point in space-time, and all information was collapsed, it can’t be done. Our ability to measure is limited by our presence in this existence. Therefore, we can only measure "that which is". God, having generated "that which is" is inaccessible, except through analogy.
At this point, I must rely, for hopefully obvious reasons, on an analogy. Think of a painter, who paints a painting. (You have to work with me here, because I’m going to posit that the painting is so good that the elements within it are somewhat aware of their environment – probably computer programmer is a better analogy, but we’ll go with painter). No element within the painting can understand the painter. Quite simply, they don’t exist in a frame of reference that can access or really have any understanding of the painter. The best the painting elements can do is extrapolate relevant principles about the painter from the nature of the painting itself.
Let’s say, however, that the painter wishes to be known to the elements of the painting. He can’t communicate via his normal means of doing so, since the painting elements, by their very natures, are unable to perceive the communication, or even the context or medium of communication – it exists outside of their accessible reality. So the only means the painter has by which to communicate is to paint within the painting something that gets the idea across. Assuming, for a moment, that the intended communication is to make the paintlets (let’s call them) know a little about him, he would have to abstract his own nature into symbolic form and paint it. And since he’s communicating with paintlets, he would have to paint himself in a way that reflects a context they could relate to. He would paint himself as a paintlet. This is a necessary inaccuracy caused by the very differences in natures of the painter and the painting. No matter how good the painter is, he can’t exceed the capacity of the medium or it becomes irrelevant.
One important point is that because there are necessary abstractions in the painter’s self-styling, the paintlets may or may not grasp the full intent of the painter’s efforts. So several variations of the self-styling are necessary to increase the information breadth, density, and context, so to allow the paintlets to better understand his communication.
So getting back to Question 2 – the reason God "paints himself" into creation through what Baha’u'llah termed "Manifestations" is that God is communicating to His sentient creation – that we might better understand him and our nature. Now part of your question is quite appropriate – we can learn tons about God from the world around us, from inspiration and extrapolation and reason. Baha’u'llah refers to these two methods of learning as the "Books of Creation and Revelation". In such ways were early spiritual beliefs appropriate, in that they abstracted knowledge of God and the universe from the world around us. We can still use this "Book of Creation" to learn about God through the vehicle of Science.
However, the reason he reveals himself explicitly through "Prophets" or "Manifestations", according to Baha’u'llah, is because humans are incapable of perceiving God directly, by reason of the differences in our nature. His Manifestations are, therefore, his self-portraits (to keep to the metaphor). They provide us with a vision of God, and God’s intentions that are increasingly complex over time. This is because we, as a species, are developing. Our understandings of things were, in earlier times, less complex, less subtle, and so on. The spiritual lessons of earlier times were also much more blunt. This, to take a rather simplistic example, is the reason that Mosaic Law could promulgate an "eye for an eye" concept of justice, which was an evolved concept compared to its precedent, but Jesus promulgated "turn the other cheek", and Baha’u'llah subsequently taught "if someone poisons your heart, sweeten their soul". These do not contradict the previous law, but call people to a higher standard. Religion, then, to the Baha’i, is an evolving thing – not because God changes, but because our capacity and needs change. More specifically, they are all teachers of one curriculum, so to speak. And in a certain sense, they are interchangeable, in that the knowledge of math could be taught by one or another teacher. They differ in the degree and couching of the lesson.
Baha’u'llah says the following in his "Book of Certitude" which is on point:
"Thus it is that Jesus, Himself, declared: "I go away and come again unto you." Consider the sun. Were it to say now, "I am the sun of yesterday," it would speak the truth. And should it, bearing the sequence of time in mind, claim to be other than that sun, it still would speak the truth. In like manner, if it be said that all the days are but one and the same, it is correct and true. And if it be said, with respect to their particular names and designations, that they differ, that again is true. For though they are the same, yet one doth recognize in each a separate designation, a specific attribute, a particular character. Conceive accordingly the distinction, variation, and unity characteristic of the various Manifestations of holiness, that thou mayest comprehend the allusions made by the creator of all names and attributes to the mysteries of distinction and unity, and discover the answer to thy question as to why 22 that everlasting Beauty should have, at sundry times, called Himself by different names and titles."
– Baha’u'llah, The Kitab-i-Iqan, p. 21
"Know of a certainty that in every Dispensation the light of Divine Revelation hath been vouchsafed unto men in direct proportion to their spiritual capacity. Consider the sun. How feeble its rays the moment it appeareth above the horizon. How gradually its warmth and potency increase as it approacheth its zenith, enabling meanwhile all created 88 things to adapt themselves to the growing intensity of its light. How steadily it declineth until it reacheth its setting point. Were it, all of a sudden, to manifest the energies latent within it, it would, no doubt, cause injury to all created things…. In like manner, if the Sun of Truth were suddenly to reveal, at the earliest stages of its manifestation, the full measure of the potencies which the providence of the Almighty hath bestowed upon it, the earth of human understanding would waste away and be consumed; for men’s hearts would neither sustain the intensity of its revelation, nor be able to mirror forth the radiance of its light. Dismayed and overpowered, they would cease to exist."
– Baha’u'llah, Gleanings from the Writings of Baha’u'llah, p. 87)
Baha’u'llah’s son `Abdul-Baha spoke the following in a gathering in London:
"Lastly the perfect man, the Prophet, is one who is transfigured, one who has the purity and 24 clearness of a perfect mirror — one who reflects the Sun of Truth. Of such a one — of such a Prophet and Messenger — we can say that the Light of Divinity with the heavenly Perfections dwells in him.
"If we claim that the sun is seen in the mirror, we do not mean that the sun itself has descended from the holy heights of his heaven and entered into the mirror! This is impossible. The Divine Nature is seen in the Manifestations and its Light and Splendor are visible in extreme glory.
"Therefore, men have always been taught and led by the Prophets of God. The Prophets of God are the Mediators of God. All the Prophets and Messengers have come from One Holy Spirit and bear the Message of God, fitted to the age in which they appear. The One Light is in them and they are One with each other. But the Eternal does not become phenomenal; neither can the phenomenal become Eternal."
– Abdu’l-Baha, Abdu’l-Baha in London, p. 23)
So when we talk about revelation to "prophets" vs. to individuals, we’re talking about two different orders of being. We are not equipped to receive revelation. The Prophets, or Manifestations are the vehicle – not the recipients – of God’s communication to us.